Muruyama Blower/sprayer

[lefty]

This is a friend's machine. Used for his business spraying for insects.

Muruyama MD830-1 (I think it's the dash-1 based on the type of throttle but I'm not sure)

Mft. No.: D1520316

I think I found the manual on this that says the engine is a Kawasaki TK65. I'm having a hard time finding numbers on this but this is my problem.

The owner brought it to me because he didn't feel it was hitting its top RPM. It does sound a little slow. My tach says 5400. I don't have the spec for it by my Husqvarna runs at about 6700 I think. I did a carb kit on it, needle diaphragms, and gaskets. Fuel lines look good. Piston and cylinder look good. Compression is about 145 (assuming that's ok). Spark arrester is clean. Trying to figure out where to go. The throttle looks like it's opening up ok and the air filter is new. Spark plug looks ok but could use a new one. Just sounds like it wants to go faster.

Thanks.

[KE4AVB]

Muruyama IPLs and Owners Manuals

Engine appears to be propriety to Muruyama.

Use Small Engines Pro Dealer to source parts.

[lefty]

Maybe a bad ignition coil? I tried to test it using a tutorial video on youtube. I checked resistance between the small wire on the coil to ground and found infinite resistance. I also checked from the spark boot end to ground and found 1.9k

The video I watched said that there should be some sort of reading on the small wire. Of course, I don't know what it should be yet but I think there's supposed to be something on the small wire? Trying to find proper specs for it. I think the part number on the coil is 649331.

The on/off switch tests ok.

I believe the small wire is the primary and the spark plug wire is the secondary? If that is the correct terminology. Does this tell me anything? The kill wire was disconnected at the time.

Thanks

Coil was installed during the test.

[RoyM]

Checck the spark arrestor in the muffler, it could be plugged with carbon. Is the customer following factory recommendations regarding mixture?

[lefty]

He's using 50:1. The spark arrester is clean.

When I said infinite resistance, I really don't know that. I just know that I got no reading with the mega ohm setting, which is my highest setting.

Here's a pic. The small wire at the bottom goes up through the grommet and connects to the coil. I'm getting no reading between the end of that wire and ground.

https://photos.app.goo.gl/gEqS97WHgA52UwBW6

[KE4AVB]

Are you saying got 1.9999 or 3.9999 or OL? or was it 0.000? The coil sound to be working.

normal operating RPM (Engine Rotational Speed) is 6350 max under load per owners manual.

[lefty]

On the mega ohm setting I got 1. Which is what it shows on an open circuit and what I usually get when it exceeds the setting. I tried all of the settings from 2 ohms all the way up to 2M. It just shows 1.

On the continuity setting, it jumped around from 1.9, 1.2, and so forth. (the setting with the little arrow pointing at a line, which I think is the continuity setting.)

So I'm about 5400 RPM now with my digital tach.

My DMM doesn't show OL. It uses 1.

[bgsengine]

My DMM doesn't show OL. It uses 1.

So, it reads a 1 when it is not connected to anything at all? how about when holding probes in your fingertips (one in each hand)? OL stands for Open Line or Open Loop , indicating infinity resistance or open circuit.. any deviation from that means there's at least some current able to flow between probes.. also want to be sure you have fresh batteries in meter... (and touch probes together should show zero resistance, or pretty close to it)

[KE4AVB]

What is the make and model of he meter? I using a Tenma 72-10405 auto ranging DVMM.

[lefty]

The meter is a sperry DM-4100A

When not connected at all, it displays 1. (instead of OL)

When connecting the leads, it displays 0.

9V battery is pretty fresh.

The resistance is high enough to not register any current at the highest setting, which is 2M. It just shows 1.

I don't know what it should be reading for this little wire, or even if it's something that would be meaningful. Just something I saw during my research. The one that the gentleman was working on was a comparable sized echo blower and he was looking for a reading of around 200 ohms.
I thought I would get the readings and then search for the spec but I haven't been able to locate it.